For instance, two things can be almost identical. They can be the same size and shape. They can provide the same benefits, or pose the same dangers. So why would one thing be cherished, while the other is feared?

Let’s take the DNA of two mammals (see below). They’re about the same size and shape. They’re closely related as species. They both live in cities. However, we perceive one as a sweet and fuzzy creature, while the other is vermin.